The present invention relates to the bioremediation (e.g., removal) of toxic compounds, and more specifically to the protection of mammals and the environment against toxic organic compounds, their related species and metabolites, especially those that result from damage or stress.
Toxic compounds can harm both humans and the environment. Toxic compounds are often referred to as xenobiotics. These compounds are generally highly toxic to life forms (including humans), are exceedingly difficult to dispose of, and are of major concern to industry (because of the cost and/or difficulty of treatment) and to regulatory agencies. Toxic compounds may be by-products of larger molecules, or may result from damage to biological molecules (e.g., stress that is drug-induced, chemically-induced, or physiologically induced). The damage may also be physiologic in nature (e.g., the result of an oxidative or alkylating nature) or be produced by radiation.
In the environment, a large source of xenobiotics arises from the manufacturing of chemicals (e.g., benzene, toluene, styrene, pesticides, dioxins, halogenated organic compounds such as pentachlorophenol and PCB, and polybrominated diphenyl ethers). Toxic environmental pollutants are often present in process waste streams, and may be present in larger quantities after spills, or in the soil and water associated with abandoned or poorly controlled industrial sites.
Environmental toxic compounds, whether in process waste streams or in spills, are now generally treated by physical, chemical or biological means. One means includes trying to physically remove the toxic materials, e.g., from air and water streams, by contacting the toxins with activated carbon particles contained within adsorption columns. A significant drawback of this approach is that the xenobiotics adsorbed onto the carbon are not destroyed, only physically removed from the contaminated stream, and therefore some subsequent disposal method to destroy the toxins must still be employed. Toxic organic compounds may also be removed by chemical means (e.g., incineration); however, this approach is costly (e.g., high temperature and pressure equipment are required) and results in the release of undesirable combustion products into the atmosphere. Therefore, there remains a need to cost-effectively process environmental toxic organic compounds without adding environmental insults or wastes into the surroundings.
Biological treatment of toxic compounds often involves the addition of the toxic material to bioreactors (i.e., tanks with aqueous microorganism suspensions) to degrade the materials to harmless end products such as carbon dioxide and water. Although potentially the lowest cost approach to xenobiotic destruction, current biological treatment of toxic organics suffers from fundamental inefficiencies. For example, the toxic material often kills the microorganisms (this is especially common with conventional wastewater treatment systems). Another drawback is that when added too slowly, microorganisms present in a biotreatment system often starve or become unable to consume the toxic compounds. Because of the above problems with current bioremediation there still remains a long-felt need to transform these toxic compounds in a more efficient, controlled, and cost-effective manner.
In mammals, toxic compounds may arise from environmental contact, from ingestion or infusion of organic or inorganic chemicals (including pharmaceutical and herbal products), and from internal oxidative damage or stress, alkylating damage, or radiation damage. Environmental contaminants, poisons, allergy producing agents and chemicals (such as pesticide residues), toxic trace elements, certain drugs and pharmaceuticals, as well as excessive levels of other non-end product metabolites that are formed in biochemical reactions in the body during states of altered metabolism are examples of compounds that may produce toxic organic compounds. Mammalian syndromes, conditions, and diseases may also lead to the accumulation of these toxic compounds, examples of which include fatigue, cancer, hypotonia, depression, lassitude, muscle weakness, insomnia, recurring bad dreams, intestinal complaints (myalgia), confusion, and functional nervous system problems.
Most mammals contain intrinsic biotransformation-detoxification pathways to rid themselves of naturally occurring toxic organic compounds; however, these physiologic pathways are only efficient when biotransformation-detoxification requirements are small. Under situations of stress (e.g., oxidative, alkylating, radiation) or when nonnatural chemicals are introduced, natural biotransformation-detoxification pathways are, themselves, often incapable, inefficient and ineffective at ridding the cell or the biologic system of the chemical. Often, the chemical may be initially transformed after which potentially toxic by-products then accumulate within the host and can prove fatal. Attempts to protect mammals from toxic accumulation of organic compounds and their by-products are generally done after chemical insult has already occurred. The addition of chemicals, foods, vitamins, nutritional supplements or drugs may be used to try to relieve the body of the excessive toxins. Most of the additives, however, are either inefficient, costly and/or have serious deleterious side effects. For mammals, these current inefficiencies and problems mean that there remains a need to aid in the protection of mammals against toxic organic compounds in an efficient, controlled, and cost-effective manner.